Deck construction



March 30, 1965 C. C. LAW

DECK CONSTRUCTION Filed 001;. 16, 1961 FIG. 3

INVENTOR. CHARLES C. LAW

3,175,653 DECK CONTRUCTIQN Charles 3. Law, 584 Youngstown-Pittsburgh Road,

Poland, Qhio Filed Oct. 16, 1.961, Ser. No. 145,061 ll 01mm. (Cl. 189-37) This invention relates to building structures and more particularly to a simplified and improved method of providing inexpensive and lightweight floor and roof deck assemblies for such structures.

The primary object of the invention is the provision of simple inexpensive structural components and readily usable methods of assembling these components into an integrated slab-like expanse suitable for floor and roof decks in building construction. Ancillary objects of the invention include reduction in cost of building structures and an increase in the speed of erection thereof.

In constructing floor and roof deck expanses, particularly where the spans between supporting walls and/ or beams are substantial, it has been common practice to utilize steel joists having top and bottom chords and intervening open webs to provide truss-like structures in which the top chord is under compression while the bottom chords are under tension. The deck material, whether concrete, composition board, or plywood and the like, is laid over the top chords of the joists, but the fastening methods heretofore employed did not admit of the transfer of any of the compressive forces to the boardlike deck material.

I have found that by taking advantage of the great edgewise compressive strength of Wide expanses of precast concrete slabs, composition board, plywood, etc., through intimately bonding such deck material at a multiplicity of spaced points to the upper extremities of truss-like joists, the compressive loads may be taken entirely by the deck material-resulting in a more rigid integrated floor or roof structure. The object here is to positively prevent any horizontal movement or creep of any portion of the deck material with respect to any portion of the truss-like supporting joists so that deflection is inhibited. Further, I have found that currently available bonding agents or adhesives have sufiicient tenacity and permanence to permit the securing of the deck material directly to the tops of the webs of the joists thereby eliminating the need for the upper chords of the joists, and correspondingly reducing the weight, cost, and space requirement factor of the joistsall of which are highly advantageous in building construction.

For a better understanding of the objects and advantages of the invention and the manner in which the same are accomplished, reference should be had to the following specification and the accompanying drawing wherein FIGURE 1 is a fragmentary perspective view of a deck assembly constructed in accordance with the principles of my invention, the view showing the board-like deck material in raised position with respect to the supporting joist;

FIGURE 2 is a fragmentary end view of a hour construction assembled in accordance with the principles of the invention; and

FIGURE 3 is a fragmentary iongitudin-al elevation of the assembly of FIGURES 1 and 2.

In FIGURES 1 and 2 the reference numeral ill desig notes the conventional lower chord of a conventional steel open-web joist, and therefore the end portions of this chord are each provided with a reverse bend to provide extreme end portions 11 which are generally parallel with the center portions of the chords it) but spaced vertically thereabove. In use, the end portions 11 rest on walls or beams to thus carry the joists in a saddled or depending relation as will be apparent to those skilled States atent in the art. In conventional practice a straight top chord, not shown herein, having the same cross-section as the chord 1t} rigidly interconnects the end portions 11 in each joist. Also in conventional practice, the top and bottom chords are rigidly interconnected by an open web commonly in the form of a bent unitary steel rod which is welded at its nodes to the chords. In FIGURES 1 and 3 herein such an open web is shown at 12 with the bottom nodes 13 thereof rigidly welded to the top surface of the chord Ill.

Welded to the centrally disposed upper nodes 14 of the web bar 12 are steel discs 15 which may be either rougherred on their upper surfaces or provided with a series of apertures 16 disposed about their peripheries as shown in FIGURE 1. Overlying the end portions 11 of the chords ill and extending inwardly toward the centers of the joist structures are metal strips 17 of suflicient iength to also overlie a plurality (three shown) of the adjacent upper nodes 14 of the web bar 12. Strips 17 are rigidly welded on their under-sides tothe portion-s11 of chords 1t and to the said adjacent nodes 14 and, again, the upper surfaces of these strips are either suitably roughened or provided with apertures throughout their lengths as shown.

In making the modified steel joist assemblies described above the bottom chords It} which may be either hotrolled sections or cold-rolled sections are first cut-to-length and reversely bent to provide the offset end portions after which the bent rods 12 are welded to the chords. Thereafter the discs 15 and the strip 1'7 may be laid out on a flat table and the as embled webs and chords placed thereon in upside-down relation and welded to the discs and strips. This arrangement insures that upon completion of the joist assemblies the top surfaces of the discs 15 and strip 17 of each joist will lie in a common plane which is important in the present invention, as will become apparent below. Of course, if it is desired to impart any degree of camber to the joists the same may be taken care of by dishing the assembly-ing table in the desired corresponding degree.

The modi. ed joists thus produced are now ready for installation in a building structure where they are commonly installed in spaced parallel relation, as shown in FIGURE 2, and wherein they span distances between walls or beams on which the end portions 11 rest. Thereafter large sheets or slabs 18 of suitable deck material such as pre-cast concrete, composition board, or plywood are overlaid on the discs 15 and strip 17 with generous layers of suitable bonding material therebetween. I have found that the epoxy resin adhesives are very well suited for this purpose since they set up very firm and strong and are permanent in their action. It will be understood that when laying down a floor or roof deck the bonding agent will be applied to the pads 15 and 17 progressively so that the firm weight of the deck material will be uniformly applied to the pads at the time the bonding agent hardens or sets up. Joints between the discrete pieces of deck material applied are made in the centers of the pads as shown at 19 in FIGURE 2.

As an alternate to the laying of the board-like deck material at the building site it may be desirable to prefabricate modules of assembled joists and deck at locations remote from the building sites, and my invention contemplates such application.

It should now be apparent that I have provided simplifled components and improved and simplified methods for making composite deck and joist assemblies suitable for use in building floor and roof structure which accomplishes the objects initially set out. By rigidly bonding the fiat slab-like deck material to the joists at a multiplicity of closely spaced points and in such manner that there is no horizontal creep between the deck and joists, the deck material will have great columnar or edgewise compressive strength suflicient to replace the upper chords of the joists as now commonly used. The complete absence of creep reduces deflection and makes for more rigid and quieter floor or roof construction. Also the Weight and cost of the joists is reduced, space is gained through elimination of the upper chords of the joists, and the floor and roof structures may be assembled with greater speed.

The above specifically described embodiment of the invention should be considered as illustrative only since many changes may be made therein without departing from the spirit or scope of the invention. Reference should therefore be had to the appended claim in determining the scope of the invention.

I claim:

A long span deck unit of the self-sustaining truss-type comprising a flat expanse of rigid sheet-like deck material, a metal bottom chord extending longitudinally of the deck material and being substantially coextensive therewith in a longitudinal direction, said chord having upwardly olfset end portions, an elongated open Web formed of a unitary length of metal rod reversely bent to form upper nodes uniformly spaced from lower nodes, said lower nodes being rigidly secured to said chord in such manner that said web lies in the plane of said chord and between the upwardly offset end portions thereof, metal strips overlying and interconnecting the top portions of said upwardly offset end portions of said chord and the top portions of the longitudinal endmost of the upper nodes of said web, discrete pads rigidly secured to the top ex tremities of the top portions of those upper nodes of the Web which are intermediate the longitudinal endmost upper nodes, and said pads and strips being rigidly bonded to the underside of the deck sheet by an adhesive.

References Cited by the Examiner UNITED STATES PATENTS JACOB L. NACHENOFF, Primary Examiner.

WILLIAM 1. MUSHAKE, HENRY c. SUTHERLAND, V

Examiners. 

